Part of Jim is still having trouble really accepting that. Even after a few years of being friends with Bones, even after all the shit they've been through so far, part of Jim still expects him to leave eventually. It's what people do, sooner or later, and it doesn't matter if it's a friend or a lover. Whether it's Bones, Hunter, or anyone else. The more rational part of him knows that it's just pessimism talking, and even if it isn't, that he should enjoy what he has while it lasts.

So he leans a little into the touch, taking what comfort he can. "Thanks."